it totally depends... our family would never use all the "extras" a gold plan provides... if you have a long trip and will be able to make use of the recreation (i.e. golf), childcare centers, cirque tix, tours, plus eat three meals a day (we rarely do on vacation... sometimes dinner is just ice cream!), etc then a gold plan may be worth it... if not, you will be spending money for things you don't do...
i would make a spreadsheet... start by making a basic "outline" for your trip then list all the options and the costs (i.e. mouseboats, $30/hour, will use for 2 hours), etc and then do a comparison... w/all the pricing/menu info on allearsnet.com you can get a pretty accurate guesstimation of cost for meals, etc...
what we're doing is a compromise of the two... we're buying the basic (5+2 dreammaker) and going for the prince/princess add-on... after doing the math, silver just wasn't worth it for us...